A wave of retirements among baby boomers in the coming decades will have a big impact on residential real estate, in ways that are upending some conventional assumptions. Baby boomers are working longer or opting for “phased” retirements, in which they work at least part time after leaving their primary careers.

They are changing the definition of a “retirement” locale, driving migration to cities with affordable housing and recreational opportunities and also robust economies that can support jobs.

It’s still true, however, that most retirees adamantly prefer to stay in their homes and communities as they age, rather than relocate. This group is choosing to alter their homes to make them easier to navigate, rather than sell them and downsize.

And while the boomers nearing retirement age are generally too young to need assisted-living facilities or similar housing, they already are having an impact on that market: They are influencing how and where those properties are built, as the decision-makers on behalf of their parents.

“Multiple trends are happening at the same time,” said Lawrence Yun, chief economist with the National Association of Realtors.

The association recently compiled an analysis of markets attractive to “leading edge” baby boomers — those 60 to 69, who are nearing or at retirement age — because they offer not just moderate climates but also affordable housing and strong economies that are attractive to self-employed people, in particular.

“I don’t discount the importance of the weather,” said Paul Irving, chairman of the Milken Institute Center for the Future of Aging, in Santa Monica, Calif., which studies how to adapt communities for older populations. “But successful aging is about more than just snow.”

While the list includes plenty of Sun Belt cities in Florida and Arizona, it also includes less obvious locations like Boise, as well as Raleigh, N.C.; Greenville, S.C.; Chattanooga, Tenn.; and McAllen, Texas, in part because housing in such places is relatively affordable and taxes are low. Such markets are attractive to baby boomers, who are moving en masse toward retirement age but don’t necessarily want to stop working all at once.

“They can trade down, using equity in their home to fund their retirement lifestyle,” Yun said. But they can also find work, if needed, to supplement their retirement savings.

Return to Boise

Shapiro, 61, said Boise filled the bill. He and his wife, Rhonda Imhoff, 53, enjoyed living in Northbrook, Ill., a northern Chicago suburb with excellent schools, and partaking of the city’s cultural resources while their children were young.

“We enjoyed all the benefits,” he said.

“But we paid for them,” both financially, in stiff property taxes, and in traffic-laden commutes.

They started visiting Boise when Imhoff’s oldest daughter decided to attend Boise State University. Imhoff had grown up in Boise but hadn’t lived there for decades and was pleasantly surprised to learn that the city had grown and changed.

“It’s a totally different place now,” she said. The city of about 214,000 people has a Shakespeare festival, and residents can see touring Broadway shows and attend sporting events at the university.

In Boise, the couple bought a single-family ranch-style home with three bedrooms: “We weren’t ready to completely downsize,” Shapiro said.

Yet the equity from the sale of their home in Chicago enabled them to buy the house with little debt, and property taxes in Boise are $10,000 less than they were in Illinois.

They kept an eye on their future needs, however, when house hunting.

“One of our nonnegotiable demands was that it had to be a single-level home,” Shapiro said, so they would not have to worry about climbing stairs when they were older. And although they chuckled nervously about it, they also made sure its hallways were “wide enough for a wheelchair.”

Such concerns are driving another trend, as retiring boomers who do not want to relocate seek to adapt their homes to their changing needs.

Most people over 65 say they prefer to stay in their own homes as they age, according to the advocacy group AARP. And, indeed, people over 65 are far less likely to move (4 percent) in a given year than those under 65 (13 percent), according to the federal Administration on Aging.

Those who do move usually stay in the same county or state; only 19 percent, for instance, moved out of state or abroad from 2012 to 2013.

But those wishes are increasingly in conflict with the scant availability of housing that can accommodate older Americans’ needs.

Fewer than a quarter of homes occupied by people 55 and older have a full complement of features, like no-step entryways, no steps between rooms, a full bedroom and bath on the first floor and wider hallways, that make them suitable for older people, according to the Joint Center for Housing Studies of Harvard University.

That suggests many homes are in for significant remodeling.

“A lot of work has to be done,” said Kermit Baker, director of the center’s Remodeling Futures Program.

Remodeling boom

It’s starting to happen. Some markets with high concentrations of people aged 55 to 64 report high spending on home improvements by households in that age group, the Harvard center found.

And spending on home improvement in 2013 was modestly higher among owners who had lived in their homes 20 years or more.

David Tate and his wife, Carol, both 65, of Yorktown, Va., retired five years ago from careers in health care. They considered moving or downsizing but decided they wanted to stay put.

Their grown children and grandchildren live close enough for frequent visits, and their five-bedroom home provides plenty of space for guests. They also relish the change of seasons, as well as the area’s rich history.

Once they made the decision to remain, they started thinking hard about the 42-year-old, two-story home where they have lived for the last 28 years.

“It was built with the needs of a family in mind,” he said, not those of an older couple.

From their career experiences — David Tate had once worked as a long-term-care executive, and his wife was a nurse — they knew the right design could make a home much more livable for aging residents.

“We knew things like, when you’re older, you need more light to see,” he said. “And grab bars in the shower are essential.”

They found a contractor certified in “aging in place” remodeling to help them redesign a bathroom with an eye toward the future. The new shower has a low curb that is easy to step into, along with a shower bench and a removable shower head that can be used while seated.

The new toilet is higher, making access easier, and it has more space around it to make it easier for someone else to assist with rising and sitting, if necessary.

Since older people often feel the cold more severely, features were added to warm up the bathroom, like radiant floor heating.

Although the Tates had paid off their mortgage, they took out a home-equity line of credit to help fund the $59,000 project, he said.

In that, they are like many older homeowners who can rely on home equity to finance some changes.

A new study from Merrill Lynch and Age Wave says more than 70 percent of homeowners over 65 have no mortgage, and home equity for homeowners over 65 averages more than $200,000. (The proportion of homeowners from 55 to 64 with no mortgage is lower, 46 percent, but this group still has average home equity of about $195,000).

Taking out a loan secured by a home to fund renovations may also allow the owner to deduct the interest on a tax return. In some cases, modifications — like lowering cabinets to make a home wheelchair-accessible — may be tax-deductible if they are medically necessary.